[mythtv] Updated patch for directshow filters with MythTV (for CoreAVC)

[Alan Nisota]

Mark Kendall wrote:
> On 2/7/07, Alan Nisota <alannisota at gmail.com> wrote:
>   
>> Andrew Lyon wrote:
>>     
>>> Its working, colours are a bit off but its playing back in realtime!,
>>> I'm going to upgrade my kernel and nvidia drivers and do more testing,
>>> ive been meaning to bring them up to date anyway..
>>>       
>> The color issue may be due to the output format we're using.  I am using
>> I420 because that is what Myth wants, but it may be that YV12 works
>> better.  If I can get a sample that shows the problem in myth, I can
>> test it in mplayer and see if I can figure out what needs to be done.
>>
>> Also, I now have multiple CPUs almost working, and it gives a huge
>> speedup.  The only problem is that I get a segfault at the end of
>> playback (inside the codec).  Once I get that worked out, I'll update
>> the patch with the fixes that have come up so far.
>>     
>
> Alan
>
> The problem is in avformatdecoder
>
> +           bih.biCompression = 0x34363268; //0x30323449;
>
> If I revert to the commented out (I420) fourcc, colourspace is as expected.
>   
This won't do what you expected.  biCompression is the input format, and 
I have it hardcoded to 'h264' at the moment (which is what CoreAVC 
wants).  We are actually interested in the output format, which is set 
just below at:
            DS_VideoDecoder_SetDestFmt(dshowdec,12,0x30323449); 
//IMGFMT_I420
however, it is not just a simple matter of changing that to YV12, as we 
need to convince myth what the format is too.  If this is the problem, 
I'll work out how to make it work, but it is much easier to test with 
mplayer where I can easily play with different modes.

I have updated the patch on ticket #3053 so it now includes the fixes 
mentioned in this thread along with multiple CPU support.